Electrical connector



1965 w. c. ELEDGE ETAL 3,199,066

ELECTRICAL CONNECTOR Filed May 27, 1963 LEONARD KATZ/N W/LL/AM C. ELEDGL INVENTORS BY &9- 3 59' 4 flaw/ W- United States Patent l 3,199,066 ELEtITRICAL CGNNECTGR William C. Eledge, unland, and Leonard Katzin, Reseda,

alif., assignors, by mesne assignments, to The Runner- Raino (Iorporation, Stamford, Conn, a corporation of Delaware Filed May 27,1963, Ser- No. 2:33AM 7 Qlairns. (ill. 339176) This invention relates to electrical connectors, and particularly to a novel connector for establishing electrical contact with circuits on a printed circuit board or the like.

Electrical connectors for use with printed circuit boards are available today in various shapes and sizes. Generally, the connector is supported by an insulating body, and the printed circuit board is inserted into the connectors. Some connectors also provide physical support for the printed circuit board as well as electrical connection, while other connectors provide only electrical connection and the printed circuit board must be supported by other means.

The problems encountered in making good electrical connection between an electrical circuit on a printed circuit board and the electrical connectors are numerous, as evidenced by the many diiierent types of electrical connectors available today. Each available electrical connector generally is the result of an attempt to solve one of the problems. However, there is still a genuine need in industry for an electrical connector which embodies the qualities of being inexpensive to manufacture, making good and continuous electrical contact with circuits on a printed circuit board, and allowing a printed circuit board to be repeatedly inserted into and removed from the connector with minimum force and without adversely altec-ting the ability of the connector to make good electrical contact.

The present invention attains the foregoing qualities by providing a unitary electrical connector which is extremely easy to fabricate, and which assures good electrical contact with a circuit board being inserted therein through the combined use of lever and spring actions. The connector preferably comprises a support having at least one outwardly extending support arm. The thickness and width dimensions of the support and the material of which it is constructed are such as to permit the outwardly extending portion of the support to have a limited spring action. A lever arm is connected approximately at its midpoint to the end of the outwardly extending support arm and is substantially parallel to the support arm. The physical connection between the end of the support and the midpoint of the lever arm is made large enough to support the lever arm but small enough to allow the lever arm limited pivotal motion in the plane of the support. A downwardly extending arm is provided to which a conductor may be attached for making electrical connection with the connector.

A series of connectors may be mounted in line on an insulating support. When a printed circuit board is inserted between the lever arms of the individual connectors and a backing member, the urging outward of the lower ends of the lever arms by the board causes the upper ends of the lever arms to be urged toward the printed circuit board because of the pivotal action of the lever arms. Also the support urges the lever arms against the printed circuit board by its spring action.

In another embodiment of the invention, the support is U-shaped to provide two outwardly extending support arms. Two lever arms are respectively connected approximately at their midpoints to the ends of the outwardly extending support arms and are urged toward each ilhhfififi Patented Aug. 3, 1965 other by spring action of the support. Thus, when a printed circuit board is inserted between the lever arms, which are substantially parallel to each other and to the outwardly extending support arms, it is firmly gripped by the connector through the combined use of lever and spring actions. It the circuit board is mounted in a series of such connectors, the connectors provide physical support for the board as well as making good electrical connection to the circuitry on the board.

Further features and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of one embodiment;

FIG. 2 is a perspective view, with part broken away, showing the connector of FIG. 1 in an assembly including a circuit board;

FIG. 3 is a perspective view of an alternate configuration of connector embodying the invention; and

FIG. 4 is a plan view of another embodiment of the invention. I

FIGS. 1 and 2 show one embodiment of the invention, in which a unitary electrical connector 19 comprises a substantially planar, U-shaped support 11 having two outwardly extending, substantially straight and parallel arms 11a and 111). Two lever arms 12a and 1212 are respectively connected to the support 11 near the outer ends of the support arms 11a, rib, by means of neck portions 13a and 13b, and are substantially parallel to the support arms 12a and 12b. Each of the lever arms is supported at a point approximately at but slightly higher than the midpoint of the arm, with neck portions 13a, 13b allowing the lever arms limited pivotal movement in the plane of the support toward and away from each other. The lever arms are mounted substantially parallel and opposite each other in the same plane and have opposed convex outer ends, the shape of the ends facilitating insertion of a printed circuit board therebetween. In addition, the lever arms are of generally concave shape toward each other and away from their respective support arms.

Extending downward from the U-shaped support 11, in a direction substantially opposite to the support arms, are a connection or contact pin 14 and a fastening or stabilizing pin 15-. The contact pin 14 and stabilizing pin 15 pass through holes 16 and 17, respectively, provided in an insulating mounting board 18. The fastening or stabilizing pin 15 may be bent over after passing through the hole 17 to secure the connector 10 to the mounting board 18. The contact pin 14 provides a convenient terminal for making electrical connection between a conductor (not shown) and the connector 10.

The connector of the invention may be made of a conventional electrically conductive material having springlike properties, such as beryllium copper (heat treated) or Phosphor bronze, which is plated with gold, silver or other material conventionally used for making good electrical contact. In a typical application, it may be about 2 inches in over-all height, one-half inch wide and 0.025-

0.030 inch thick.

A series of connectors may conveniently be mounted between insulating alignment bars 19 which are secured to the mounting board 18. The bars 19 are provided with slots 20 to accommodate the connectors, with the slots being large enough to allow limited movement of the connector portions 11a and 1*1'b toward and away from each other. Of course, the slots 20 in each bar 19 are spaced apart to match the circuits on a printed circuit board with which contact is to be made; for example, they may be on one-eighth or one-tenth inch centers. The alignment bars 19 also restrict the connectors 10 from making electrical contact with each other.

As best seen in FIG. 2, a printed circuit board 21 may be inserted between the lever arms of a series of connectors mounted between two boards 19. It should be noted that as the printed circuit board 21 is inserted into the connector, it first forces the lever arms 12a and 12b apart at their upper or outer ends. Then, as the printed circuit board is inserted farther into the connector, it forces the lower or inner ends of the lever arms apart, thereby applying a pivotal force about the neck portions 13a and 13b (which act as pivot points) to urge the tops of the lever arms against the printed circuit board. The spring action of the U-shaped support 11 also urges the lever arms 12a and 12b against the printed circuit board 21.

When the length of each lever arm below its pivot point is longer than its length above the pivot point and the upper ends of the lever arms are closer together than the lower ends (without a circuit board inserted therebetween), and a circuit board 21 is inserted, the upper ends of the lever arms are urged against the board with more force than the lower ends of the lever arms. The upper ends. of the lever arms therefore provide the basic electrical contact with the printed circuit board, and the action of both upper and lower ends contributes to physical support of the board. The printed circuit board is held in position by the electrical connectors and no other support is necessary to hold the circuit board in position, provided enough connectors are used and the printed circuit board is of a reasonable size. However, external support for the printed circuit board can be used, if desired.

The insertion of a printed circuit board into the connector is relatively easy because a very little applied force spreads apart the upper ends of the lever arms 12a and 1212. This is so because they pivot about the pivot points defined by the neck portions 13a and 13b and because the lower ends of the lever arms are not yet forced apart. Once the printed circuit board is inserted past the upper ends of the lever arms, additional force is needed to further insert and seat the printed circuit board. However, such force may be applied without fear of damaging the printed circuit board because of the generally concave shape of the lever arms 12a and 12b, and because displaced terminal on the other side of the printed circuit board. The forces urging the lever arms 12a and 12b against a printed circuit board are the same, whether the lever arms are in the same plane or in parallel planes,

assuming that the circuit board is sufiici-ently stilf so as not to be bent by the forces exerted by the connector.

A simplified version of the connector of the invention is shown in FIG. 4, which. shows a connector 23 that is, in effect, only half of the connector 10 shown in FIG. 1. The connector 23 provides the same type of lever and spring action as the connector 10 in FIG. 1, except that the force of the connector is applied to only one side of a printed circuit board. The other side of the printed circuit board may be supported either by another connector similar to the connector 23 or simply by a backing member, such as one of the alignment bars 19 (FIG. 2).

The connectors of the invention, when used with a mounting boar-d and alignment bars in a manner such as shown in FIG, 2, provide a multi-contact electrical connector arrangement, wherein excellent electrical connections with a printed circuit board are made continuously,

even under conditions of severe vibration. The connectors, when used as set forth above, allowed a printed All circuit board to be repeatedly inserted and removed with minimum force and without adversely affecting the ability of the connectors to make electrical contact. The connectors are extremely inexpensive to manufacture, such as by stamping, and can be made to accommodate various sizes of printed circuit boards.

Although several embodiments of the invention have been shown and described, it is apparent that many changes may be made by one skilled in the art without departing from the true spirit and scope of the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An electrical connector useful for contacting an electrical conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of electrically conductive, resilient material and comprismg:

a base portion adapted to be fixedly held by the support means;

an elongated arm portion extending from said base portion in a direction generally away from said base portion and away from the surface of said support means when said base portion is held thereby and is resiliently movable with respect thereto, said arm portion having an extension near that extremity thereof which is remote from said base portion; and

an elongated contact portion supported at a position longitudinally intermediate its extremities and on a first side thereof by said arm portion by means of the extension thereon, said contact portion extending generally parallel to and being spaced apart from said arm portion and pivotally movable with respect thereto about said extension, said contact portion having a first and a second contact area delineated on a second side thereof which is opposite said first side, said contact portion being recessed between said cont-act areas so that a plane tangent to said contact areas is also generally parallel to said arm portion but with that part of said second side intermediate said contact areas being recessed from said tangent plane.

2. An electrical connector useful for contacting an electrlcal conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of electrrcally conductive, resilient material and comprising:

a base portion adapted to be fixedly held by the support means;

an elongated arm portion extending from said base port1on 1n a direction generally away from said base portion and away from the surface of said support means when said base member is held thereby and is resil ently movable with respect thereto, said arm portion having an extension near that extremity thereof which is remote from said base portion; and

an elongated contact portion supported at a position longitudinally intermediate its extremities and on a first side thereof by said arm portion by means of the extension thereon, said contact portion extending generally parallel to and being spaced apart from said arm portion and pivotally movable with respect thereto about said extension, said contact portion having a first and a second contact area delineated on a second side thereof which is opposite said first side, said contact portion being recessed between said contact areas so that a plane tangent to said contact areas is also generally parallel to said arm portion but with that part of said second side intermediate said contact areas being recessed from said tangent plane, the position of said contact portion support being intermediate said contact areas with said first contact area being more remote from said base portion but closer to said position of said contact portion support than said second contact area.

3. An electrical connector useful for contacting an electrical conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of elec trically conductive, resilient material and comprising:

a base portion adapted to be fixedly held by the support means:

an elongated arm portion extending from said base portion in a direction generally away from said base portion and away from the surface of said support means when said base portion is held thereby and is resiliently movable with respect thereto, said arm portion having an extension near that extremity thereof which is remote from said base portion; and

an elongated contact portion supported at a position longitudinally intermediate its extremities and on a first side thereof by said arm portion by means of the extension thereon, said contact portion extending generally parallel to and being spaced apart from said arm portion and pivotally movable in the plane of said connector with respect thereto about said extension through resilient deformation of said connector substantially in said extension, said contact portion having a first and a second contact area delineated on a second side thereof which is opposite said first side, said contact portion being recessed between said contact areas so that a plane tangent to said contact areas is also generally parallel to said arm portion but with that part of said second side intermediate said contact areas being recessed from said tangent plane.

4. An electrical connector useful for contacting an electrical conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of electrically conductive, resilient material and comprising:

a base portion adapted to be fixedly held by the support means;

first and second elongated parallel arm portions extending from said base portion in a direction generally away from said base portion and away from the surface of said support means when said base portion is held thereby and said first and second arm portions being resiliently movable with respect thereto, said arm portions each having an extension near that extremity thereof which is remote from said base portion and the extensions directed towards one another; and

first and second elongated contact portions each supported at a position longitudinally intermediate its extremities and on a first side thereof by each of said arm portions by means of the extension thereon, each of said contact portions extending generally parallel to and being spaced apart from said arm portion and pivotally movable in the plane of said connector about said extension, each of said contact portions having a first and a second contact area delineated on a second side thereof which is opposite said first side with the first contact areas facing one another and the second contact areas facing one another, and each of said contact portions being recessed between said contact areas so that the planes tangent to the first and contact areas are also generally parallel to the arm portions but with that part of said second side of each of said contact portions intermediate said contact areas being recessed from said tangent plane.

5. The connector as defined in claim 4 wherein the first and second arm portions and the first and second contact portions are disposed substantially in a single plane.

6. An electrical connector useful for contacting an electrical conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of electrically conductive, resilient material and comprising: a base portion adapted to be fixedly held by the support means; first and second elongated parallel arm portions extending from said base portion in a direction generally away from said base portion and away from the surface of said support means when said base portion is held thereby and said first and second arm portions being resiliently movable with respect thereto, said arm portions each having an extension near that ext-remity thereof which is remote from said base portion and said extensions directed towards one another; and first and second elongated contact portions each supported at a position longitudinaly intermediate its extremities and on a first side thereof by each of said arm portions by means of the extension thereon, each of said contact portions extending generally parallel to and being spaced apart from said arm portion and pivotally movable in the plane of said connector about said extension, each of said contact portions having a first and a second contact area delineated on a second side thereof which is opposite said first side with the first contact areas facing one another and the second contact areas facing one another, and each of said contact portions being recessed between said contact areas so that the planes tangent to the first and second contact areas are also generally parallel to the arm portions but with that part of said second side of each of said contact portions intermediate said contact areas being recessed from said tangent plane, the position of each contact portion support being intermediate the contact areas with said first contact area being more remote from said base portion but closer to said position of the contact portion support than said second contact area.

7. An electrical connector useful for contacting an electrical conductor upon a circuit-bearing board or the like and adapted to be supported and extend away from the surface of a support means made of electrically insulative material, said connector being made from a sheet of electrically conductive, resilient material and comprising:

a base portion adapted to be fixedly held by the support means; 7 first and second elongated parallel arm portions extending from said base portion in a direction generally away from said base portion and away from the surface of said support means when said base portion is held thereby and said first and second arm portions being resiliently movable with respect thereto, said arm portions each having an extension near that extremity thereof which is remote from said base portion and said parallel arm portions each substantially planar but disposed in spaced parallel planes; and first and second elongated contact portions each supported at a position longitudinally intermediate its extremities and on a first side thereof by each of said arm portions by means of the extension thereon, each of said contact portions extending generally parallel to and being spaced apart from said arm portion and each being pivotally movable in the plane of the respective arm portion about the extension thereof, each of said contact portions having a first and second contact area delineated on a second side thereof which is opposite said first side and each of said contact portions being recessed between said contact areas so that the planes tangent to the first and second contact areas are-also generally parallel to the respective arm portions but with that part of said second side of each of said contact portions intermediate said contact areas being recessed from the respective tangent plane.

(References on following page) References Cited by the Examiner UNITED STATES PATENTS 10/59 Gilbert 339-47 5/60 Kennedy 339 17 5 8/60 Johanson et a1. 339--220 7/61 Fox 339-17 8 FOREIGN PATENTS JOSEPH D. SEERS, Primary Examiner. 

1. AN ELECTRICAL CONNECTOR USEFUL FOR CONTACTING AN ELECTRICAL CONDUCTOR UPON A CIRCUIT-BEARING BOARD OR THE LIKE AND ADAPTED TO BE SUPPORTEDF AND EXTEND AWAY FROM THE SURFACE OF A SUPPORT MEANS MADE OF ELECTRICALLY INSULATIVE MATERIAL, SAID CONNECTOR BEING MADE FROM A SHEET OF ELECTRICALLY CONDUCTIVE, RESILIENT MATERIAL AND COMPRISING: A BASE PORTION ADAPTED TO BE FIXELY HELD BY THE SUPPORT MEANS; AN ELONGATED ARM PORTION EXTENDING FROM SAID BASE PORTION IN A DIRECTION GENERALLY AWAY FROM SAID BASE PORTION AND AWAY FROM THE SURFACE OF SAAID BASE MEANS WEHN SAID BASE PORTION IS HELD THEREBY AND IS RESILIENTLY MOVABLE WITH RESPECT THERETO, SAID ARM PORTION HAVING AN EXTENSION NEAR THAT EXTREMITY THEREOF WHICH IS REMOTE FROM SAID BASE PORTION; AND AN ELONGATED CONTACT PORTION SUPPORTED AT A POSITION LONGITUDINALLY INTERMEDIATE ITS EXTREMITIES AND ON A FIRST SIDE THEREOF BY SAID ARM PORTION BY MEANS OF THE EXTENSION THEREON, SAID CONTACT PORTION EXTENDING GENERALLY PARALLEL TO AND BEING SPACED FROM SAID ARM PORTION AND PIVOTALLY MOVABLE WITH RESPECT THERETO ABOUT SAID EXTENSION, SAID CONTACT PORTION HAVING A FIRST AND A SECOND CONTACT AREA DELINEATED ON A SECOND SIDE THEREOF WHICH IS OPPOSITE SAID FIRST SIDE, SAID CONTACT PORTION BEING RECESSED BETWEEN SAID CONTACT AREAS SO THAT A PLANE TANGENT TO SAID CONTACT AREAS IS ALSO GENERALLY PARALLEL TO SAID ARM PORTION BUT WITH THAT PART OF SAID SECOND SIDE INTERMEDIATE SAID CONTACT AREAS BEING RECESSED FROM SAID TANGENT PLANE. 